Why does a song sometimes get stuck in our heads – and what precisely makes an earworm?

The series in which readers answer other readers’ questions explores an ancient, vexed musical conundrum• Readers reply: to shred or not to shred? Is it OK to throw out sensitive documents?I know a song that’ll get on your nerves, get on your nerves, get on your nerves. I know a so … you get the gist! Why does a song sometimes get stuck in our heads? (And good luck stopping this one now!) Laura Ashton, Haslemere, SurreyPost your answers (and new questions) below or send t